msem-instigator

Create a 1/1 red Goblin creature token and a 2/2 white Knight creature token.
Tether to artifact (Then if you cast this from your hand, you may exile it tethered to an artifact you control. When it dies, you may cast this from exile without paying its mana cost.)

Mosecf, the Sunseeker's Path enters tapped.
Whenever a creature you control attacks, put a creation counter on Mosecf.
{T}, Remove ten creation counters from Mosecf and sacrifice it: Creatures you control get +2/+2 and gain vigilance until end of turn. Activate only as a sorcery.

Return target creature to its owner's hand. Create a 2/2 green Bear Actor creature token.

Equipped creature gets +2/+2.
Whenever equipped creature attacks, each opponent who controls more artifacts than you sacrifices an artifact. Opponents sacrifice creatures, enchantments, lands, and planeswalkers the same way.
Equip {1}{W}

Trample
When Descendant of Shimaru enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Creature spells you cast cost {1} less to cast for each of their creature types that no creature you control has.
Whenever you cast a creature spell, if it has a creature type no creature you control has, draw a card.

Flying
Whenever Souls of the Jury enters or an opponent fails a trial, create a 1/1 white Cleric creature token.

Flying, prowess
Whenever you cast a noncreature spell, untap Ingenious Trickster.

Equipped creature gets +1/+1.
As long as equipped creature is a Soldier or Warrior, it gets an additional +1/+1.
Equip {1}

Create two 1/1 blue Bird creature tokens with flying and “When this creature dies, draw a card.”

Colossal 4—{5}{U}{U}{U} (You may cast this for its colossal cost to have it enter with four +1/+1 counters; or pay {5}{U}{U}{U} as a sorcery: Put four +1/+1 counters on it if it has none.)
Whenever Megalokraken enters or attacks, reveal the top X cards of your library, where X is Megalokraken's power. You may cast a noncreature spell with mana value X or less from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.

Flash
When Leafdown Ambusher enters, create three colorless artifact tokens named Arrow. They have “{T}, Tap an untapped creature you control, Sacrifice this permanent: The tapped creature fights target creature you don't control. Activate only as a sorcery unless this permanent entered this turn.”

Flash
When Priority Paradigm enters, conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)
The first sorcery spell you cast each turn has flash.

Draw a card. Create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Choose three. You may choose the same mode more than once.
• Each opponent sacrifices a creature.
• Each opponent loses 2 life and you gain 2 life.
• Choose a player and look at their hand. Choose a nonland card from among them. They discard it.

Whenever an artifact you control is put into a graveyard from the battlefield, create a 4/4 red Dragon creature token with flying.

Changeling (This card is every creature type.)
Watcher of the Polyps has all names of creature cards in addition to its name as long as it's on the battlefield.
Watcher of the Polyps gets +X/+X, where X is the greatest number of creatures you control with the same name.

Young Dragonheart gets +1/+0 and has first strike as long as you control a legendary creature.

Reach (This creature can block creatures with flying.)
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Flying
Nonartifact permanents entering the battlefield don't cause abilities to trigger.

Reach

Whenever Aravant Smuggler deals combat damage to an opponent, if it's embattled, draw a card. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

Target player discards two cards.
Rerun (If you cast this from your hand, exile it as it resolves. Whenever a creature you control dies, you may cast this card from exile without paying its mana cost.)

At the beginning of your upkeep, if you have less life than an opponent, you lose 1 life and you draw a card.

Creatures you control get +1/+1 until end of turn. Token creatures you control get an additional +1/+1 until end of turn.